1. Field of the Invention
The present invention relates to cartridges such as toner cartridges, image drum cartridges, ink ribbon cartridges, and ink cartridges for use in printers, facsimile machines, and copying machines. The present invention also relates to a method of manufacturing these cartridges, and further to an image forming apparatus into which the above-described cartridges are attached.
2. Description of the Related Art
Conventional cartridges of the same construction and appearance have projections or cut-away portions different in shape from cartridge to cartridge, so that a cartridge can be identified from many other cartridges of the same appearance. The cartridge may have an area to which a seal is attached, so that users can identify the content in the cartridge.
However, the manufacture of cartridges having a portion of different shapes necessitates slightly different molds from cartridge to cartridge. This is uneconomical and an obstacle to the mass production of cartridges.
With the cartridge having a seal attached thereto, the user may inadvertently load an inappropriate cartridge into the printer. The use of an inappropriate cartridge causes poor image quality and trouble of machine operation.
The present invention was made in view of the aforementioned drawbacks and an object of the invention is to provide a cartridge where an image forming apparatus can detect the content of a cartridge when the cartridge is loaded therein.
In order to achieve the aforementioned object, the cartridge according to the present invention has a combination of magnets by which the content of the cartridge can be identified.
A cartridge is attached to an image forming apparatus that performs a printing operation only when the cartridge is a predetermined kind of the cartridge. The cartridge comprises a first predetermined number of magnet holders provided on the cartridge and a second predetermined number of magnets each of which is received in a corresponding one of the magnet holders. A maximum value of the second predetermined number is equal to the first predetermined number. A combination of the magnet holders having the magnets therein indicates the kind of the cartridge.
The image forming apparatus comprises a detector section and an identifying section. The detector has magnetic sensor elements each of which detects a magnetic flux of a corresponding one of the magnets. The identifying section compares reference data with a combination of outputs of the magnetic sensor elements so as to identify the kind of the cartridge.
Another image forming apparatus uses the aforementioned cartridge and a second cartridge attached thereto. The second cartridge includes a first detector that has first magnetic sensor elements, each of the first magnetic sensor elements detecting a magnetic flux of a corresponding one of the magnets of the first cartridge. The first cartridge includes a first predetermined number of magnet holders and a second predetermined number of magnets received in the magnet holders. A maximum value of the second predetermined number is equal to the first predetermined number. A combination of the magnet holders having the magnets received therein indicating a kind of the cartridge.
The image forming apparatus comprises a second detector and an identifying section. The second detector has second magnetic sensor elements, each of the magnets of the second magnetic sensor elements detecting a magnetic flux of a corresponding one of the magnets of the first cartridge. The identifying section determines contents of the first and second cartridges on the basis of outputs of the first and second magnetic sensor elements.
A method is used for manufacturing a cartridge having magnet holders that hold magnets attached thereto. The method comprising attaching at least one magnetic element into a corresponding one of the magnet holders formed of a non-magnetic material, the magnetic element not having been magnetized yet; and placing the cartridge in a magnetic field to magnetize the magnetic element.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.